By my recollection, concrete drainage ditches are often played as ground under repair. I was a little surprised when the scorecard at Mission Trails indicated on the scorecard that they should be played as a lateral hazard.
I was in one on #8 today at RBI, and I checked the scorecard. The scorecard says "Holes #1, 2, and 18 concrete channel is defined as an immovable obstruction." On those holes, I thought that drainage ditch would play as a yellow hazard. But there's nothing noted for hole #8, so I took an unplayable lie.
Digging through the official rules, the definition of Penalty Area includes a drainage ditch (even if not containing water). So I guess I took the proper penalty (1 stroke), but for the wrong reason (penalty area versus unplayable lie).